New user and first "crossbow"

Brand new here and want to thank everyone for all the useful information. My crossbow was built with the knowledge from this website and the wiki it links to on the right side so thank you for that. Please excuse my lack of knowledge in regards to terminology I will try to get everything right but still pretty new to this whole world.

That being said I have been toying around with this project for some time now. I started out with a couple wood prods that would toss a bolt like a soft ball pitch. The firing mechanism worked well though so that was pretty cool.

I just "upgraded" to a leaf spring prod that I got the dimensions for on the same wiki.http://crossbow.wikia.com/wiki/Plan_for_a_simple_leaf-spring_prod

My layout was just a hair smaller (first metal prod and I was very nervous) and I also have a much shorter draw length (only about 10"). I was hoping to get in around 100# draw weight (website estimated roughly 150# off the layout and roughly 15" draw length) but it ended up coming in around 65#.

I have it braced at just under 4".

Couple questions:Will it stack up that much weight in the last 5" or so of draw or am I missing something?

Draw length is measured from the back of the prod to full draw and power stroke is measured from string at brace to full draw (sorry if I am butchering the crossbow speak)?

I have read that when cutting out the prod you have to watch heat so you don't effect temper... Well I read that after I went to town with my angle grinder. I went really slow since I am not really comfortable with the angle grinder but that being said I never quenched the metal or gave heat a second thought. Could I have messed something up here?

With the increase in weight the nut has stripped out on the bottom were the trigger catches. I am thinking of replacing this with an Oak nut and reinforcing it with a strip of metal. Am I on the right track or will this just strip out same as last? (I think the last nut was left over poplar dowel from a closet that wasn't reinforced at all)

Well with that all being said (and hopefully I get this posting right) here is a picture of my work in progress.

What a pretty little bow!As for the temper, if you didn't get it much above boiling I wouldn't worry too much, if you got it red hot then I'd worry about the temper. Others will help out on this topic.As for the nut, yeah a bit of steel goes a long way. I use a band saw to cut a notch, then press the steel in. Another way would be to use a pin with a side files flat where the lever touches.

Let me know if you want to switch to a delrin nut. I have been offering these to folks for the cost of shipping. I still have some left. Once I order more, then I'll ask some money for it. It seems that making the nut is the most daunting for some, so I offer it as a service. I have easy access to a lathe and it takes no time at all to do. I'll face it 1" wide and drill an undersize center hole.

That is really generous of you phu and thank you for the compliments on the bow

I will try the metal insert although I have considered very strongly using delrin. Is that stuff that tough to work with? I figured I could attack it with a decent file set and hack saw. I was thinking of hitting up my local suppliers and see if any of them have any cut scraps laying on the floor to experiment with.

It is really nice to work. It cuts like butter, and is slippery. A file, saw, and drillpress will work it easily. A way to face off the end without a lathe is to center drill it, run a bolt through it, and tighten up a nut to keep it clamped. Then put a bit of sandpaper on the drill press table, chuck the bolt into the, er, chuck...ahem, and gently lower it onto the paper. That will make a good face on the side of the wheel, and make a lot of plastic dust. Don't overheat it, though.

That is a really good looking bow! The stirrup looks pretty good, almost looks like its part of the prod. Been wondering about starting a new bow along those lines, but as i found out today, you can't order steel or glass prods to portugal, probably some imports law or something. Gonna have to start looking for leaf springs i guess.

Mhof86; getting back to your prod. I doubt very much that you damaged the temper. If you did ,I think that when you pulled to the draw length. it would have mostly stayed bent right there.It wouldn't have any power so to speak.

Thanks for the kind words JoaoLS. I was surprised how easy it was to get the leaf spring apart and shaped out. This one I got from the salvage yard down the road out of his "scrap" pile and I still have 2 more leaves that are big enough for prods. Whole spring cost me $10. Considering I don't mess up the other two that's not to bad for 3 prods.

C Sitas, I haven't noticed the prod taking any set (if that translates over to crossbows) and the power from first shot to now (maybe 100 shots) has not dropped off at all.

I was wondering though if leaving it strung will hurt the prod? It's a real bear stringing it.

No ,it doesn't hurt to leave it strung. One thing , where it and your string are new it's probbally helping you by taking the thretch out of your string.You can keep a close watch on your prod by checking the fistmle height once in a while. That is where the story is.